Cosmoline
Member
The D166 is a very interesting bullet. It has a tapered body and a "belt" around the waist that is a slightly wider diameter. I've found shooting D166 handloads does not cause the same fouling as shooting straight surplus .311" ball. I'm having best luck using Varget with it but I'm still tweaking the loads.
Another one that seems to work well with the Finn bores is the surplus Polish light ball that has a hollow base and is somewhat narrower than most surplus. It's been shooting very well out of my M39.
